Due to the perfection of the nanofabrication in nanotechnology and nanoscience, ice lithography (IL) by patterning ice thin-films with a focused electron beam, as a significant derivative technology of electron beam lithography (EBL), is attracting growing attention, evoked by its advantages over traditional EBL with respects of in situ-fabrication, high efficiency, high accuracy, limited proximity effect, three-dimensional (3D) profiling capability, etc. However, theoretical modeling of ice lithography for replicated profiles on the ice resist (amorphous solid water, ASW) has rarely been reported so far. As the result, the development of ice lithography still stays at the experimental stage. The shortage of modeling methods limits our insight into the ice lithography capability, as well as theoretical anticipations for future developments of this emerging technique. In this work, an e-beam induced etching ice model based on the Monte Carlo algorithm for point/line spread functions is established to calculate the replicated profiles of the resist by ice lithography. To testify the fidelity of the modeling method, systematic simulations of the ice lithography property under the processing parameters of the resist thickness, electron accelerating voltage and actual patterns are performed. Theoretical comparisons between the IL on ASW and the conventional EBL on polymethyl methacrylate (PMMA) show superior properties of IL over EBL in terms of the minimum feature size, the highest aspect ratio, 3D nanostructure/devices, etc. The success in developing a modeling method for ice lithography, as reported in this paper, offers a powerful tool in characterizing ice lithography up to the theoretical level and down to molecular scales.

中文翻译：

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无定形固体水冰光刻的理论建模

由于纳米技术和纳米科学的纳米加工技术的完善，通过聚焦电子束对冰薄膜进行图案化的冰光刻（IL）作为电子束光刻（EBL）的重要衍生技术，正受到越来越多的关注。在原位制造、高效率、高精度、有限的邻近效应、三维 (3D) 分析能力等方面优于传统 EBL. 然而，迄今为止，很少报道冰刻蚀剂（无定形固体水，ASW）上复制剖面的冰光刻理论建模。因此，冰光刻的发展还停留在实验阶段。建模方法的缺乏限制了我们对冰光刻能力的洞察力，以及对这种新兴技术未来发展的理论预期。在这项工作中，建立了基于蒙特卡罗算法的点/线扩散函数的电子束诱导蚀刻冰模型，以通过冰光刻计算抗蚀剂的复制轮廓。为验证建模方法的保真度，系统模拟了抗蚀剂厚度、电子加速电压和实际图案等工艺参数下的冰刻性能。等等。如本文所述，成功开发冰光刻建模方法为在理论水平和分子尺度上表征冰刻提供了强大的工具。